Thermostat issue. 2009 S3

[J0N]

Last time my car was in a dyno I was told my thermostat was getting ready but I never got around to changing it, this was back in December and I’ve only noticed the needle drop slightly below 90° a couple of times since.
Recently though I checked my oil temp on the DIS and it doesn’t rise above 46° with the engine up to temp. Could a faulty thermostat be causing this?


Sent from my iPhone using Tapatalk

 

[LEE69]

No, the oil temp should be about 90 ish and higher if using the engine more shall we say
Not sure where the oil temp sensor is on these, could be the sump or the oil pump housing, or an oil way

 

[J0N]

I’m struggling to find the oil temp sensor too, I would’ve thought it’d be on the block but I can’t find any info on it.


Sent from my iPhone using Tapatalk

 

[J0N]

Also, if I turn off the engine then turn the ignition back on to check the oil temp it rises above 70° but rapidly decreases. I know this can’t be the ‘actual’ temperature, it’s a weird one.


Sent from my iPhone using Tapatalk

 

[Bryant1998]

My temp gauge was dropping to 70/80 when pushed hard, I thought revo cai was magically helping intake temps drop but when it went to r-tech they said to do the rear engine temp sensor (£120 I think?)
That’s made my engine temp reading stay at 90 now

(They called me while it was there asking if my engine temp ever dropped when pushed hard and said it was easier and cheaper to do while having the walnut blast done as the labour for accessing it is essentially already been paid for so was just charged for the part)

 

[J0N]

Yeah it’s looking like an awful job to change the thermostat. The more I look into it though I’m swaying towards the oil temp sensor but I’m struggling to find it’s location. I’m thinking the temp might be read by the oil level sensor in the sump but I’m by no means sure??


Sent from my iPhone using Tapatalk

 

[Bryant1998]

Not a clue mate sadly, but if you haven’t had the walnut blast and injector clean I’d recommend it highly, made my car feel so much better and you can get the sensor changed for peace of mind (and long term saving on labour)

 

[ab1702]

I’d you go on a website called cardiagn.com it has all the manuals with instructions in for the car that you can download for free as a pdf. I’ve been looking as I were thinking to change the thermostat on mine because the temperature gauge is always moving and hardly ever stays at 90 although as someone said above it seems to be a big job.